The invention relates to a device for letting off residual steam and residual water from the heating unit of a hot beverage machine, for example a coffee machine.
With known fluid systems in coffee machines and other hot beverage machines, it is generally desirable to remove any residual water in the heating unit which remains after the coffee extraction or the hot water release. Once the machine is turned off, such residual water is vaporized into steam as a result of existing residual heat or is present in the form of residual water and/or flash water, and is allowed to collect in a collection container that is generally installed inside the coffee machine. The same steps are taken if, following the process of generating steam to supply to a steam nozzle or a frothing nozzle, the heating unit is cooled down with fresh water until it reaches a temperature for preparing coffee. That is to say, unused steam and, if necessary, hot water are also released into the collection container. The steam generated during this operation is also referred to as residual steam or flash steam since its pressure is reduced as compared to the steam generated during the operation, in particular through opening a residual fluid line and shutting down a water pump which otherwise pumps fresh water into the heating unit that is typically designed as a flow-through heating unit.
A corresponding device, known from practical operations, for letting off residual steam, comprises a residual fluid line which is connected via an on-off valve to the heating unit, so as to conduct fluids, and which leads to a collection container in the coffee machine. The disadvantage of this device is that some of the residual steam within the coffee machine can escape uncontrolled and can thus affect components inside the coffee machine, particularly the electronic components. These components can be damaged and/or can fail completely and undesirable micro-biological cultures can form even faster. The removal of the residual steam and residual water outside of the housing generally was not planned because of the related danger of scalding.